The present invention relates to an automatic vehicle component assembly system, and more particularly, to an automatic decking and automatic fastening (ADAF), apparatus and method that effects automatic decking and automatic fastening of vehicle body components to vehicle chassis components.
One of the most impressive operations in a vehicle assembly plant involves the marriage of a vehicle body structure to its chassis. For a pick-up truck, this process is generally subdivided into assembly of the passenger cab to the frame and assembly of the utility box to the frame. Commonly used methodology involves a substantial reliance upon manual intervention to accomplish this complex task. In the case of a pick-up cab, a subassembly that can weigh in the neighborhood of 1200 pounds (545 kilograms), is supported by equipment and manually guided into position to align or xe2x80x9cjustifyxe2x80x9d the cab relative to the frame, before lowering it onto the frame to effect decking. In addition, manpower is used to guide the machinery that individually applies the fasteners for securing the components together. Automating this type of vehicle assembly process is highly desirable due to the labor intensive and physically demanding operations involved.
Aspects of the present invention involve automation of the process that decks and secures a vehicle body component to its chassis. In accordance with these aspects, an automatic decking and automatic fastening system includes a base with an elevatable unit repositionable relative to the base by at least one actuator. Preferably, the elevatable unit is compliant in the fore-aft direction. This preferred fore-aft compliance is useful in accommodating any experienced chassis carrier stopping error. A cross-car slidable unit is supported on the elevatable unit and is repositionable relative to the elevatable unit by at least one other actuator. Preferably, this other actuator can stop and hold position when an element of the chassis such as a frame bracket has been located. Tooling (referred to in the following detailed description of the preferred embodiment as an ADAF plate), is carried on the slidable unit and is repositionable vertically relative to the slidable unit by yet another actuator. The tooling locates off the chassis element and serves to carry and to justify the body component to the chassis. A fastener driver is preferably carried by a compliant assembly on the slidable unit. This assembly allows the fastener driver to have a preferred compliance in the cross-car and fore-aft directions relative to the slidable unit, and allows the fastener driver, with its own lead in tooling, to locate a mounting fastener.
According to preferred aspects of the present invention, the body element is positioned in space at a predetermined location. The actuators are operated to reposition the tooling to accept and justify the body element to a position determined by engagement of the tooling with the chassis. The justified body element is lowered to the chassis, the tooling is retracted, and the fastener driver advances fastening the body element to the chassis.